Metal stress is a very common phenomenon for aircraft's main material, pressure changes with ascending
and descending altitude and presurization usually flexes the metal by expanging it and contracting it, which causes material weakening. This natural process is normal and happens during every plane's life, however in the most extreme cases, excessive metal stress can cause an explosive decompression.
Accidents involving metal stress[]
- On April 28, 1988 an Aloha Airlines Boeing 737-200 lost a 3rd part of it's roof while flying at cruise altitude.